The Dnestr M radar at Skrunda 1 was a giant fixed antenna that watched the sky for missiles without any moving parts. It sat on a long building about 200 meters across. The beam moved by changing the frequency of the signal it sent out. Different frequencies pointed the narrow beam left or right across a 30 degree sector. When an echo came back the time delay gave the distance and the frequency used gave the direction. The radar sent long pulses that were later compressed for better accuracy. This simple method let the Soviets cover the western approaches from Latvia during the Cold War. The whole station closed in 1998 and the buildings are empty now. It remains one clear example of how early warning worked before modern radars.